Hybrid electric vehicles generally use an internal combustion engine and one or several electric drives. Optimization-based energy management strategies computes a power split between both the engine and the machine to minimize the fuel consumption. Nevertheless, the driving comfort is not taken into account. Due to its high torque bandwidth, the electric machine can be used to improve driving comfort. The objective of this paper is to propose the use the electric machine to actively damp the encountered side-shafts torque oscillations. The driveshaft torsional behavior is described and the corresponding comfort issues are highlighted. Simulations results have been done for the nominal case and to validate the controller behavior with respect to some un-modeled parameter variations.